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Here we show how a lattice Boltzmann based approach accurately model acoustic wave propagation in strongly heterogeneous media. Rather than solving a partial-differential wave equation in a continuous medium, the lattice-Boltzmann based method directly simulates the physical processes of wave propagation: transportation, reflection and transmission. It can accurately handle sharp interfaces at any locations along lattice links, and total reflections from free surfaces or empty bubbles. I used empty and nonempty bu...

Nowadays, airborne electromagnetic methods are widely used to investigate subsurface areas. One of these methods is helicopter electromagnetic method. The basis of inverse modeling of frequency-domain HEM data is to solve Mundry’s integral numerically. Various methods have been invented for numerical solution of this integral, such as Laplace transform, fast Hankel coefficients and Jacobian methods. To analyze helicopter electromagnetic data, we need inverse programs which can assist us to achieve the best or ac...

Electromagnetic (EM) methods are among geophysical methods which have many various applications. Besides, EM surveys are carried out rapidly with low costs. Thus, they are being fast developed. The methods, compared to other geophysical methods, have the most various acquisition systems. EM surveys can be carried out in the land, air, sea and borehole. During 1950s in Canada, airborne EM methods, in which helicopter EM (HEM) method is also included, have assisted in mineral exploration valued more than 10 milliard...

In this article we investigated a practical case history to define and show the differences of sand and gravel in side scan sonar images. The images were obtained by the Yellow- Fin side scan sonar instrument and processed with related software. The sound transmitted by the DSL-120 kHz instrument travels to the seafloor, bounces off of the seafloor, returns to the instrument, and is recorded. The strength of the sound recorded by the side-scan sonar instrument converted to shades of gray. A very strong return is w...

The causes of geomagnetic disturbances are either high velocity streams of solar wind originating in coronal holes or coronal mass ejections related to solar energetic events. In this presentation we will concentrate on the second case. Data concerning solar energetic events, published by the USAF/NOAA in the form of daily reports, have been collected since 1996. An analysis of ten years long data collection has shown that the degree of the geoeffectiveness of energetic events depends not only on their size and on...

The method of seismic refraction is widely used in many applied Geology fields and problems today. Although it has some limitations, in the case of detecting a lower velocity bounded layer, this method is well tailored to a crystalline environments where, more often, weathering degree is highest on the surface and gradually decreases in depth and thus can aid in associating the weathering degree to velocity. Some relationships have been made to establish a connection between velocities and the elastic properties o...

Several soft-programs to reverse tomography data acquired on 2D panels, for transmitted seismic rays, were developed. The procedures are based on three concepts: graphic mediation of velocities (V) coupled with a system of correction factors to reconstruct the initial V distribution (Tomography Interactive Modeling-TIM), minimize velocities errors by applying matrix calculation (Matrix Calculus in Tomography -MCT) and graphic-analytical uncover of velocities from the periphery to the center of the examined panel (...

The historical Ibrahim Aga Mansion purchased by the Chamber of Architects of Aksaray and wished to be used as the service building for the chamber. In this study, the strengthening project before the restoration of the building was prepared. The building had no foundations under the stone walls and suffered from cracks and decaying of the wooden floors. Since the existing structural system did not allow restoration of the building, strengthening and redesign of the structural system was the main priority. In the r...

Horizontal location and interpretation of gravity anomalies plays an important role in the detection of anomalous bodies and determination of explorative boreholes location. There are various methods for interpreting of gravity anomalies, which commonly use high-pass filters. Among these, Normalized Full Gradient (NFG) method represents the full gradient of the gravity anomaly at a point divided by the average of the full gradient at the datum. This method uses Fourier series to remove deficiencies and eliminate t...